In short
- Spring Boot reduces the need to write a lot of configuration and boilerplate code.
- It has an opinionated view on Spring Platform and third-party libraries so you can get started with minimum effort.
- Easy to create standalone applications with embedded Tomcat/Jetty/Undertow.
- Provides metrics, health checks, and externalized configuration.
You can read more here http://projects.spring.io/spring-boot/